An imaging lens includes: in order from an object side, an aperture diaphragm; a first lens of a positive lens having a convex surface on the object side; a second lens of a meniscus lens having a concave surface on the object side; and a third lens. The imaging lens satisfies: f/f3<0.95 and BR2<0. BR2 satisfies BR2=A/D 4 , A represents a distance from a vertex position on a object-side surface of the second lens and on an optical axis to a position on a image-side surface of the second lens through which a light ray passes toward a corner of an image height, provided that a traveling direction of the light ray is taken as appositive direction, and D 4 represents a center thickness of the second lens. f represents a focal length of the imaging lens. f3 represents a focal length of the third lens.
1. An imaging lens of a three-lens configuration, comprising: in order from an object side
an aperture diaphragm;
a first lens of a positive lens having a convex surface on the object side;
a second lens of a meniscus lens having a concave surface on the object side; and
a third lens,
the imaging lens satisfying conditional expressions:
f/f 3<0.95 (1)
BR 2<0 (2)
wherein
BR2 satisfies BR2=A/D 4 , A represents a distance from a vertex position on a object-side surface of the second lens and on an optical axis to a position on a image-side surface of the second lens through which a light ray passes toward a corner of an image height, provided that a traveling direction of the light ray is taken as appositive direction, and D 4 represents a center thickness of the second lens,
f represents a focal length of the imaging lens, and
f3 represents a focal length of the third lens.
2. The imaging lens according to claim 1 , further satisfying a conditional expression:
0.22<( D 3+ D 4) /f< 0.43 (3)
wherein D 3 represents a surface spacing between an image-side surface of the first lens and an object-side surface of the second lens along the optical axis.
3. The imaging lens according to claim 2 , further satisfying a conditional expression:
vd 2>40 and −1.2 <f 3 /f< 0.0 (4)
wherein vd2 represents an Abbe number of the second lens at the d-line.
4. The imaging lens according to claim 1 , further satisfying a conditional expression:
vd 2>40 and −1.2< f 3 /f< 0.0 (4)
wherein vd2 represents an Abbe number of the second lens at the d-line.
5. The imaging lens according to claim 1 , further satisfying a conditional expression:
vd 2>40 and 0.0< f 2 /f< 2.0 (5)
wherein vd2 represents an Abbe number of the second lens at the d-line; and f2 represents a focal length of the second lens.
6. The imaging lens according to claim 1 , wherein the third lens is negative.
7. An imaging lens comprising: in order from an object side
an aperture diaphragm;
a first lens of a positive lens having a convex surface on the object side;
a second lens of a meniscus lens having a concave surface on the object side; and
a third lens,
the imaging lens satisfying conditional expressions:
f/f 3<0.95 (1)
D 4 /f< 0.136 (6)
D 6 /f≦ 0.155 (8)
wherein D 4 represents a center thickness of the second lens; f represents a focal length of the imaging lens; D 6 represents a center thickness of the third lens; and f3 represents a focal length of the third lens.
8. The imaging lens according to claim 7 , further satisfying a conditional expression:
−0.5 <f 1 /f 2<−0.1
wherein f2 represents a focal length of the second lens.
9. The imaging lens according to claim 7 , further satisfying a conditional expression:
0.22<( D 3 +D 4) /f< 0.43 (3)
wherein D 3 represents a surface spacing between an image-side surface of the first lens and an object-side surface of the second lens along an optical axis.
10. The imaging lens according to claim 7 , wherein the third lens is negative.
11. An imaging lens comprising: in order from an object side
an aperture diaphragm;
a first lens of a positive lens having a convex surface on the object side;
a second lens of a meniscus lens having a concave surface on the object side; and
a third lens,
the imaging lens satisfying conditional expressions:
f/f 3<0.95 (1)
D 4 /f< 0.136 (6)
wherein D 4 represents a center thickness of the second lens; f represents a focal length of the imaging lens; and f3 represents a focal length of the third lens,
further satisfying a conditional expression:
f 3 /f<− 0.4 and −5.6 < f 2 /f<− 3.3 (10)
wherein f2 represents a focal length of the second lens.
12. An imaging lens comprising: in order from an object side
an aperture diaphragm;
a first lens of a positive lens having a convex surface on the object side;
a second lens of a meniscus lens having a concave surface on the object side; and
a third lens,
the imaging lens satisfying conditional expressions:
f/f 3<0.95 (1)
D 4 /f< 0.136 (6)
wherein D 4 represents a center thickness of the second lens; f represents a focal length of the imaging lens; and f3 represents a focal length of the third lens, further satisfying a conditional expression:
vd 2>40 and −1.2 <f 3 /f< 0.0 (4)
wherein vd2 represents an Abbe number of the second lens at the d-line.
13. An imaging lens comprising: in order from an object side
an aperture diaphragm;
a first lens of a positive lens having a convex surface on the object side;
a second lens of a meniscus lens having a concave surface on the object side; and
a third lens,
the imaging lens satisfying conditional expressions:
f/f 3<0.95 (1)
D 4 /f< 0.136 (6)
wherein D 4 represents a center thickness of the second lens; f represents a focal length of the imaging lens; and f3 represents a focal length of the third lens, further satisfying a conditional expression:
f 3 /f<− 1.66 and 0.1< |f 1 /f 2|<0.5 (11)
wherein f2 represents a focal length of the second lens.
14. An imaging lens comprising: in order from an object side
an aperture diaphragm;
a first lens of a positive lens having a convex surface on the object side;
a second lens of a meniscus lens having a concave surface on the object side; and
a third lens,
the imaging lens satisfying conditional expressions:
f/f 3<0.95 (1)
D 4 /f< 0.136 (6)
wherein D 4 represents a center thickness of the second lens; f represents a focal length of the imaging lens; and f3 represents a focal length of the third lens,
further satisfying a conditional expression:
022<( D 3 +D 4) /f< 0.43 (3)
wherein D 3 represents a surface spacing between an image-side surface of the first lens and an object-side surface of the second lens along an optical axis, and further satisfying a conditional expression:
vd 2>40 and ( D 4 +D 6) /f< 0.31 (7)
wherein vd2 represents an Abbe number of the second lens at the d-line; and D 6 represents a center thickness of the third lens.
15. The imaging lens according to claim 14 , further satisfying a conditional expression:
D 6 /f≦ 0.155 (8).